Foldable bed



2 Sheets-Sheet 1 VII-- R. A. SALZER FOLDABLE BED Feb. 22, 1955 Filed June 21, 1949 1x1 EN TOR. R0001. PH 4. 5/71. 25/? A 7TO/QNEY.

Feb. 22, 1955 R. A. SALZER 2,702,392

FOLDABLE BED Filed June 21, 1949 2 Sheets-Sheet 2 A TTOR/VEK United States Patent FOLDABLE BED Rudolph A. Salzer, New York, N. Y.

ApplicationJune' 21, 1949, Serial No. 100,323

4 Claims. (Cl. -230) The present invention relates to beds of the type having a frame and a flexible sheet connected to the frame by means of helical springs.

It is the principal object of this invention to construct relatively light-weight beds of the above type, which will be sturdy in use and rigid under a load placed on the flexible sheet.

The above and other objects and advantages are accomplished in accordance with the invention by providing a two-section bed, wherein each section is formed of two rigid, outwardly convex side bars and a straight element connecting the outer ends of the side bars, a straight reinforcing member being fastened to and extending between the ends of each side bar, and the flexible sheet forming the resting support of the bed is fastened to the frame, by means of coil springs, a longitudinal element being arranged in the coil springs to limit their extension under a load.

Preferably, the two sections are connected by pivoted joints to make the bed foldable.

The straight reinforcing members for each convex bar will prevent the bars from being bent when a load is placed on the flexible sheet, even when the bars are made of relatively light-weight material. The limiting element in the coil springs will keep the springs from being overextended and will, therefore, maintain the spring action even of helical springs made of thin wires. The use of such thin helical springs is preferred since they have great elasticity and thus make the resting surface of the bed more comfortable.

The various features of the invention will be more particularly described in conjunction with some preferred embodiments shown in the accompanying drawing, wherein Fig. 1 is a perspective view of a foldable bed;

Fig. 2 is a top plan view thereof (with certain parts omitted);

Fig. 3 is a top plan view of the bed frame;

Fig. 4 is a perspective view showing an embodiment of the spring fastening means of the invention; and

Figs. 5-8 are fragmentary side and top plan views, respectively, showing other modifications of the invention.

Referring now to the drawing, the bed frame is shown to consist of two sections, each of which is made of out wardly convex side bars 1 and 2, respectively, each of bars 1 and 2 being joined pivotably at 3. The pivotable joint makes it possible to fold the frame. Flexible sheet 4, which constitutes the beds resting surface, is fastened to the frame by helical springs 6.

The frame is supported at its four corners by legs 2' and at its center by legs 3', the legs being braced by rods 4 and 5'.

As shown in Fig. 3, the ends of the convex side bars 1 and 2 are connected by a straight reinforcing member 5. These reinforcing members stifien the side bars against inward pressure and prevent them from being deformed by a load placed on the flexible sheet 4.

The flexible sheet 4 is fastened to the frame by means of thin helical springs 6 to make the resting surface as comfortable as possible, since such springs will assure ready yielding of the sheet under the load of a person resting on the bed. Such springs are preferably made of the finest tool steel and should be no thicker than about 0.0551. Such thin springs, which insure a soft lying surface, ordinarily stretch too much when a relatively heavy load is repeatedly applied thereto. The

2,702,392 Patented Feb. 22, 1955 extension of the springs is, therefore, kept within predetermined limits in accordance -with a further feature of the invention.

As shown in Fig. 4, rods or wires 8 extend through the convolutions of the helical springs, one end of each rod being connected to the sheet 4, while the other end is bent to form stop 9. When a heavy load is placed on sheet 4, the extension of spring 6 will be halted when stop 9 engages the last coil of spring 6 as it slides inwardly through the spring as a result of the loads pressure. Thus, spring 6 will be prevented from stretching beyond its elastic limit and its spring action will be maintained. In addition, rod 8 will also keep the spring from twisting and turning under heavy pressure.

As shown in Figs. 5-8, the frame may also be open at one end, i. e. one end of the bed may be resilient rather than rigid. In this embodiment, the rigid connecting element is replaced by a flat spring 10 attached to the convex side bars in straight-line bearings 11. The bearings allow the flat spring to move only in a longitudinal direction, which limits the bending of the spring under a load placed on the flexible sheet 4.

If a person lies on a bed of the latter construction with his feet on the flat spring, the spring will give and make it more comfortable for the person than if his feet rested on the rigid connecting element.

The sheet 4 may be connected to spring 10 in any suitable manner. As shown in Figs. 6 and 7, it is wound around the spring in loop 13. In Fig. 8, the sheet is shown to be attached to the spring by means of spring members 12.

What I claim is:

1. A bed comprising a frame having two sections, each section including two substantially rigid side bars and one straight element connecting the outer ends of the bars, each side bar being formed as an outwardly convexed arc; means for joining two longitudinally adjacent bars at their other ends to form said frame; a substantially straight reinforcing member fastened to and extending between the ends of each bar; a flexible sheet; a plurality of spaced coil springs fastened with one end along the two longitudinal edges and at least one lateral edge of the flexible sheet and with the other end to said side bars and a respective one of said connecting elements; and a longitudinal element extending through the convolutions of each coil spring and having its ends in operative connection with ends of the spring to limit the extension of the spring under a load.

2. A bed comprising a frame having two sections, each section including two substantially rigid side bars and one straight element connecting the outer ends of the bars, each side bar being formed as an outwardly convexed arc; means for joining two longitudinally adjacent bars at their other ends to form said frame; a substantially straight reinforcing member fastened to and extending between the ends of each bar; a flexible sheet; a plurality of spaced coil springs fastened with one end along the two longitudinal edges and at least one lateral edge of the flexible sheet and with the other end to said side bars and a respective one of said connecting elements, and rod extending through the convolutions of each coil spring, the rod being attached to the sheet at one end and having its outer end bent over to confine the sprang convolutions when the spring is extended under a 3. A bed comprising a foldable frame having two sections, each section including two substantially rigid side bars and one straight element connecting the outer ends of the bars, each side bar being formed as an outwardly convexed are; means for pivotally joining two longitudinally adjacent bars at their other ends to form said frame; a substantially straight reinforcing member fastened to and extending between the ends of each bar; a flexible sheet; a plurality of spaced coil springs fastened with one r end along the two longitudinal edges and at least one lateral edge of the flexible sheet and with the other end to said side bars and a respective one of said connecting elements; and a longitudinal element extending through the convolutions of each coil spring and having its ends in operative connection with ends of the spring to limit the extension of the spring under a load.

4. A bed comprising a frame having two sections, one section including two substantially rigid side bars and a straight rigid element connecting the outer ends of the bars, and the other section including two substantially rigid side bars and a straight blade spring connecting the outerends of the bars, each of said side bars being formed as anoutwardly convexed arc; means for joining two longitudinally adjacent bars at their other ends to form said frame; a substantially straight reinforcing member fastened to and extending between the ends of each bar; a flexible sheet; a plurality of spaced coil springs fastened with one end along the two longitudinal edges and at least one lateral edge of the flexible sheet and with the other end to said side bars and a respective one of said connecting elements, and a longitudinal element extend- 15 4 ing through the convolutions of each coil spring and having its ends in operative connection with the ends of the spring to limit the extensionof the spring under a load.

References Cited in the file of this patent UNITED STATES PATENTS 541,872 Neely July 2, 1895 1,308,601 Meditz July 1, 1919 1,503,391 Teske July 29, 1924 FOREIGN PATENTS 425,757 France Apr. 13, 1911 502,091 Germany July 11, 1930 574,600 Great Britain Jan. 11, 1946 

